Tires Lose Pressure

[psyflyjohn]

Yesterday morning, as I was set to leave the driveway, I noticed the "Tire Problem" icon was lit. The first thing that occurred to me was that I had a slow leak puncture. Hey ! I would get to use their cheezy puncture kit, which replaces the spare tire.

But it turned-out to be low air pressure in all the tires. Thinking back, I realized that I had not checked the pressure since getting the car in March. Also, my mileage had been slowly dropping, and I was noticing a "mushiness" in cornering. The pressure in each tire was 30 lb., and should be 36 lbs. Inflating the tires to the recommended pressure quickly solved the difficulties noted above.

Lesson learned. These tires remind me of bicycle tires more than auto tires, and seem to lose pressure more easily than the old gasser. Check the pressures once a month, as the manual recommends. The Miev is a low maintaince car - not no maintenance, though.

 

[JoeS]

Agree with that. I run 60psi and check it every few weeks and sure enough the pressure is invariably down a few psi every time.

 

[Don]

Every car I have with alloy wheels (which is all of them) lose a pound or two of pressure each month or so. I don't check them every week or anything, but I regularly check every tire in the garage (3 cars, 3 bikes) at least every 6 weeks or so . . . . while I have the comprssor hose out, I do them all. I run 45 pounds in the Mitsu tires

Don

 

[psyflyjohn]

Wow ! 45 and 60 lbs !! Doesn't that make the tires rock hard?
Must make for a rough ride, not to mention the stress on the suspension. (what there is of it)

 

[NeilBlanchard]

The tires are rated (sidewall max) at 51PSI -- pump them up and roll better and farther; and drive farther per charge. The ride may be firmer, and the suspension can take it.

 

[JoeS]

Wow ! 45 and 60 lbs !! Doesn't that make the tires rock hard? Must make for a rough ride, not to mention the stress on the suspension. (what there is of it)

I first started running high tire pressures way back when I was active in autocrosses and gymkhanas in my Austin Healey, as "subjectively" I felt this improved the car's handling. The fuel mileage benefit was incidental in those days.

"Normal" tire pressures feel mushy to me, and I do indeed subjectively believe that the iMiEV's handling is improved. Yes, I keep an eye on the roadway and avoid potholes and protruding manhole covers, but the iMiEV's suspension is just fine, thank you.

Don, and here I was about to make a wisecrack about casting porosity being the possible culprit to gradual pressure loss, as my Gen1 Insight also has this issue whereas the steel rims of the other cars don't.